1 // RUN: %clangxx_dfsan %s -fno-exceptions -o %t && %run %t
2 // RUN: %clangxx_dfsan -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 %s -fno-exceptions -o %t && %run %t
3 //
4 // REQUIRES: x86_64-target-arch
5 //
6 // Use -fno-exceptions to turn off exceptions to avoid instrumenting
7 // __cxa_begin_catch, std::terminate and __gxx_personality_v0.
8 //
9 // TODO: Support builtin atomics. For example, https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html
10 // DFSan instrumentation pass cannot identify builtin callsites yet.
11 
12 #include <sanitizer/dfsan_interface.h>
13 
14 #include <assert.h>
15 #include <atomic>
16 #include <pthread.h>
17 
18 std::atomic<int> atomic_i{0};
19 
20 struct arg_struct {
21   size_t index;
22   dfsan_origin origin;
23 };
24 
ThreadFn(void * arg)25 static void *ThreadFn(void *arg) {
26   if (((arg_struct *)arg)->index % 2) {
27     int i = 10;
28     dfsan_set_label(8, (void *)&i, sizeof(i));
29     atomic_i.store(i, std::memory_order_relaxed);
30     return 0;
31   }
32   int j = atomic_i.load();
33   assert(dfsan_get_label(j) == 0 || dfsan_get_label(j) == 2);
34 #ifdef ORIGIN_TRACKING
35   if (dfsan_get_label(j) == 2)
36     assert(dfsan_get_init_origin(&j) == ((arg_struct *)arg)->origin);
37 #endif
38   return 0;
39 }
40 
main(void)41 int main(void) {
42   int i = 10;
43   dfsan_set_label(2, (void *)&i, sizeof(i));
44 #ifdef ORIGIN_TRACKING
45   dfsan_origin origin = dfsan_get_origin(i);
46 #endif
47   atomic_i.store(i, std::memory_order_relaxed);
48   const int kNumThreads = 24;
49   pthread_t t[kNumThreads];
50   arg_struct args[kNumThreads];
51   for (int i = 0; i < kNumThreads; ++i) {
52     args[i].index = i;
53 #ifdef ORIGIN_TRACKING
54     args[i].origin = origin;
55 #endif
56     pthread_create(&t[i], 0, ThreadFn, (void *)(args + i));
57   }
58   for (int i = 0; i < kNumThreads; ++i)
59     pthread_join(t[i], 0);
60   return 0;
61 }
62